Hi Parkash
I am doing a PhD and have spent about 2 years or more attemting 
to do what you are carrying out- I was looking at spinal ligaments 
in the human - and on poorly fixed tissue -so you are well ahead in 
terms of achieving your goal.
One thing you may want to conside if all else fails is 
cholinesterase staining for wholemount- its very simple, sensitive 
and extremely good at picking up the sort of plexuses you are 
trying to see.  If you want to further details don't hestiate to contact 
me - I'm working over Xmas
Keep going & good luck with the immuno
Gill Johnson